How Escalators Work

­Escalators are one of the largest, most expensive machines people use on a regular basis, but they're also one of the simplest.

At its most basic level, an escalator is just a simple variation on the conveyer belt. A pair of rotating chain loops pull a series of stairs in a cons­tant cycle, moving a lot of people a short distance at a good speed.

In this article, we'll look inside an escalator to find out exactly how these elements fit together. While it is exceedingly simple, the system that keeps all the steps moving in perfect synchrony is really quite brilliant.

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What's in a Name?

Early escalators were known by a variety of names, including "travelling staircase," "inclined elevator" and "magic stairway." Around 1900, Charles Seeberger, who designed the forerunner of the modern escalator, came up with the name that finally stuck. His term "escalator" is a combination of "elevator" and "scala," the Latin word for steps.